Question: Luis ate 1 slice of pie. Brandon ate 4 slices. If Luis ate $\dfrac{1}{10}$ of the pie, what fraction of the pie is remaining?
Explanation: If 1 slice represents $\dfrac{1}{10}$ of the pie, there must have been a total of 10 slices. $\text{fraction of pie remaining} = \dfrac{\text{number of slices remaining}}{\text{number of slices total}}$ Together they ate 5 slices, which leaves 5 out of 10 slices remaining. There is $\dfrac{5}{10}$ of the pie remaining.